With the development of network and Internet technology and the rapid propagation of mobile communication terminals such as smart phones, various services using audio or video have been provided over a network. Further, along with these services, as methods of determining the identicalness of audio or video, there have been widely used methods using a fingerprint, and there have been proposed technologies for recognizing various pieces of audio or video using fingerprints over a network.
Technologies for recognizing audio or video using fingerprints are implemented using a method of generating the feature vectors of frames while dividing a given audio or video signal into frames, and of performing matching using the feature vectors. Such a conventional fingerprint generation and matching method is problematic in that the computational complexity is high, so that time is required to generate and match fingerprints, and a load is imposed on network resources. In order to solve this problem, the number of fingerprints to be generated may be decreased, or a matching process may be simplified, but this results in the problem of deteriorating matching accuracy.
Korean Patent Registration No. 10-0456408 (Date of Publication: Nov. 10, 2004) relates to an “Audio gene generation method and audio data search method”, and discloses an audio gene generation method including the time division step of dividing an audio signal into regular time intervals; the frequency conversion step of calculating the magnitudes of frequency signals at regular time intervals or included in a plurality of time intervals; the difference calculation step of dividing a frequency domain into predetermined sections and calculating differences between the magnitudes of signals present in neighboring frequency sections; the gradient calculation step of obtaining a difference between the calculated values in neighboring time intervals; the quantization step of quantizing a value to 1 when the gradient is equal to or greater than 0, and to 0 when the gradient is less than 0; and the audio gene generation step of storing the quantized values and generating audio genes.
However, this technology is limited in that the computational complexity is high, and the fingerprint extraction procedure is complicated, thus imposing a load while requiring an excessively long time to calculate results.
Therefore, there is required the development of a fingerprint extraction and matching method that are capable of providing accurate results within a short period of time without imposing a load.